Ranjith

Delayed expansion of amalgam is associated with the following two factors?

Select two answers

• Insufficient trituration and condensation

• High residual mercury

• Contamination of amalgam during trituration and condensation

• Failure to use cavity varnish

High copper amalgam is preferred over low copper amalgam because of the undesirable clinical properties present in which phase

• Gamma

• Gamma one

• Gamma two

• Eta phase

Which of the following is true regarding polishing of amalgam?

Select all that apply

• reduces marginal discrepancy

• Should be done 10 mins after placement of amalgam

• Occlusion should not be checked before polishing

• Prevents tarnish and corrosion

• Improves the appearance of the restoration

Factors to be considered regarding selection and placement of amalgam restoration, except one?

• High copper amalgam over low copper amalgam

• Increased trituration time will increase the strength and decrease the setting expansion compared to decreased setting time

• Ideal mercury content should be between 55-60%

• Smaller the particle size less the expansion

• Compressive strength is more in amalgam compared to tensile strength

Strongest phase of dental amalgam?

• Gamma phase

• Gamma One

• Gamma two

• Eta phase

What is true regarding Creep?

Select all that apply

• Creep happens over a time

• Creep increases the marginal integrity of amalgam

• Rate of creep increases in Under trituration

• Over trituration decreases the rate of creep

• Increasing the condensation pressure decreases the creep

Choose statement that correctly defines the term AMALGAM?

• Amalgam is a metallic powder composed of silver, tin, copper and zinc 

• Amalgam is an alloy of two more metals that have been dissolved in each other 

  in the molten state

• Amalgam is an alloy of two or more metals, one of them is mercury 

• Amalgam is an alloy of two or more metals, one of them is tin 

Addition of Zinc in Amalgam alloy powder?

• 1. Increases Hardness

• Scavanger

• Adds colour to the amalgam

• Increases the setting expansion

Percentage of copper in admixed amalgam?

• 2-5%

• 9-20%

• 13-30%

• 6-12%

Loss of strength in silver amalgam restoration sufficient to cause fracture of the 

restoration. 

• Over trituration

• Heavy condensation pressure

• Use of small particles in amalgam

• High mercury content in set restoration